Mithrodia bradleyi

Lore & Background

Bradley's sea star has five arms that are banded in lighter and darker shades of red or red-brown. Its disk is small, and the arms are covered with many small bumps and fewer, more prominent spines. The spines are arranged in rows, including a row along the top of each arm and typically two more rows running the length of the arms on either side. The arms are rounded, almost circular in cross-section. The sea star can obtain a diameter of 20 centimetres.

This species lives in the eastern Pacific Ocean from Mexico to Chile, including the Gulf of California and the Galapagos Islands. It inhabits rocky bottoms and coral reefs from the intertidal zone to 50 metres deep. The water temperature band for this animal is from 19.74 °C to 24.327 °C, which is cooler than a typical tropical fish tank, so it is not collected for the aquarium trade.

Reader's Guide

Mithrodia bradleyi is notable for its distinctive banded red coloration and the arrangement of spines in rows along its arms. Its description by Addison Emory Verrill in 1870, based on a specimen collected by Frank Howe Bradley in Panama, ties it to early scientific exploration of the eastern Pacific. The species' distribution from Mexico to Chile, including the Galapagos Islands, and its habitat on rocky bottoms and coral reefs, highlight its ecological range. The specific temperature band (19.74 °C to 24.327 °C) is cooler than typical tropical fish tanks, which explains its absence from the aquarium trade. The maximum diameter of 20 centimetres and the rounded, almost circular cross-section of its arms are key physical traits. The species' common name, Bradley's sea star, honors the collector of the type specimen. No further significance or legacy is provided in the source article.

Did You Know?

• Bradley's sea star was first described by Addison Emory Verrill in 1870.
• The species was named after Frank Howe Bradley, who collected the type specimen in Panama.